Furfural was prepared through the combined hydrolysis of rice hull with cellulase and SO 4 2--TiO 2 clay solid acid. An optimization analysis of the key factors was carried out with the methods of orthogonal experimentation and response surface analysis. The orthogonal experiment result of enzymolysis showed that the average pentose content was 17.54 g L -1 under the following conditions i.e., granularity of raw materials, 120 grit; solid-to-liquid ratio, 1:13; zymohydrolysis temperature, 55 °C; enzymolysis time, 8 h and amount of enzyme solution, 30 U g -1 dry rice hull powder. The response surface analysis of the preparation of furfural with solid acid showed that the yield of furfural was 70.87 % under a reaction temperature of 152 °C, reaction time of 125 min and 6.1 % of solid acid. Compared with the technology that does not use cellulase hydrolysis, the yield of furfural was increased by 18.41 %.

Yu X.-C.,Yue Yang Vocational and Technical College | Sun D.-L.,Central South University of forestry and Technology | Li X.-S.,University of South ChinaAsian Journal of Chemistry | Year: 2012

Ultrasound-enhanced supercritical CO 2 was used to extract the essential oil of masson pine. The extraction technology was optimized through orthogonal experiments. The results showed that a good outcome can be achieved with an extraction pressure of 18 MPa, a temperature of 60 °C, a time of 90 min, a CO 2 flow rate of 12 kg h -1, an ultrasonic power of 250 W and an ultrasonic frequency of 22 KHz. Using these parameters, the average yield of essential oil was 88.12 %. GC-MS analysis showed that the ingredient with the highest content of 44.42 % was longifolene in the essential oil of masson pine wood, followed by a-pinene and caryophyllene, with contents of 28.17 and 6.03 %, respectively.

Yu X.-C.,Yue Yang Vocational and Technical College | Yu X.-C.,Central South University of forestry and Technology | Sun D.-L.,Yue Yang Vocational and Technical College | Sun D.-L.,Central South University of forestry and Technology | And 2 more authors.Asian Journal of Chemistry | Year: 2010

Levulinic acid was prepared from cellulase and SO4 2--TiO2/clay solid acid synergistic hydrolysis for rice straw. Orthogonal experiment and response surface methodology were applied to carry out optimum analysis on main parameters. The aim of this study is to obtain the optimal reaction conditions needed to degrade rice straw by cellulase and to synthesize levulinic acid with solid acid. The orthogonal experiment result shows that when the reaction temperature is 50 °C, the volume of the enzymolysis solution is 30 U g-1 of dried straw powder, the vibration reaction time is 8 h, the raw material granularity is 80 grit and the average content of reducing sugar is 15.67 mg mL-1. Response surface analysis indicates that under a reaction temperature of 215.94 °C, a reaction time of 34 min and a solid acid dosage of 7.10 %, the levulinic acid yield can reach 23.52 %. The synergistic hydrolysis of cellulase and SO4 2--TiO2/clay solid acid on rice straw had the benefit of increasing the levulinic acid yield. The existing reaction conditions are mainly the same as the experimental reaction conditions. As compared to the technology without the use of cellulase hydrolysis, the method in this study produced levulinic acid with 4.79 % increased yield.

Yu X.-C.,Yue Yang Vocational and Technical College | Yu X.-C.,Central South University of forestry and Technology | Sun D.-L.,Central South University of forestry and Technology | Sun D.-B.,Central South University of forestry and Technology | And 2 more authors.Wood Science and Technology | Year: 2012

Sun D.-L.,Central South University of forestry and Technology | Yu X.-C.,Yue Yang Vocational and Technical College | Sun D.-B.,Central South University of forestry and TechnologyWood and Fiber Science | Year: 2010